These appliances produce pulses the duration of which is generally comprised between 5 and 80 ms, which is exceptionally long for a flash and, for this raison, presents specific heat dissipation problems.
In this type of appliance, the high-power flashlamps (dedicated to phototherapy) for dispensing an intense pulsed light have a water cooling system. Typically, the xenon tube is immersed in a closed cavity in which the cooling liquid circulates. This liquid is circulated by a pump. It passes into a radiator in order to allow heat diffusion. The radiator is associated with a large, powerful fan.
One of the drawbacks of the water cooling systems is the requirement to guarantee a perfectly watertight circuit, in particular at the lamp. This systematically results in an increase in the bulk and weight of the appliance. Moreover, pollution of the cooling liquid regularly occurs, which leads to pollution of the lamp (walls). Premature ageing of the lamp makes it necessary to change the lamp, resulting in more frequent unavailability of the appliance.
A need therefore exists for compact appliances that do not have the major drawbacks linked to a water cooling circuit.